Ground effect machine



4, 1 R. T. HURLEY ET AL 3,066,753

GROUND EFFECT MACHINE Filed Feb. 26, 1960 4 Sheets-Sheet l lNVENTofR-z/ ROV r HUAZL F7 4 [Oh/4 2D 5. 46

ATTORNEVS Dec. 4, 1962 R. T. HURLEY ETAL GROUND EFFECT MACHINE 4 Sheets-Sheet 2 Filed Feb. 26, 1960 mmvrozas Roy 7? HURLEV BY [Bk/4R0 .5. ,46/V/ 22M 247 ATTORNEYS Dec. 4, 1962 R. T. HURLEY ET AL GROUND EFFECT MACHINE Filed Feb. 26, 1960 4 Sheets-Sheet 3 INVENTORS ROY 7? HURLEY BY EDA/4RD .5. ,46N/

ATTORNE'VS 1962 R. T. HURLEY ET AL 3,066,753

GROUND EFFECT MACHINE Filed Feb. 26, 1960 4 Sheets-Sheet 4 INVENTORS ,eay 77 HU/QL EV EDA/5W0 .5. AGN/ 3,65%,753 Patented Dec. 4, 1952 3,066,753 GROUND EFFECT MACHINE Roy T. Hurley, Saddle River, NJ, and Edward S. Agni, Dearborn, Mich, assignors to Curtiss-Wright Corpora-= tion, Utica, Mich, a corporation of Delaware Filed Feb. 26, 1960, Ser. No. 11,183 2 Claims. (Cl. 180-4) This invention relates to air supported vehicles in general and more particularly to air supported vehicles for amphibious use.

Air supported vehicles, as the term is hereinafter used, refers to vehicles which are elevated and held suspended above a supporting surface on a column or pad of air under pressure and are capable of relatively frictionless movement over land, water or any other relatively unobstructed supporting surface. Such vehicles are distinguishable from flying vehicles making use of air foil principles and marine craft which incorporate hydra foil principles, except as such principles may be used to further extend the versatility of an air supported vehicle.

Since air supported vehicles ride or float above the terrain over which they travel, the air supporting surface may be land, water, marsh, sand tundra, ice or snow. The pressurized air which supports the vehicle and holds it aloft escapes under the vehicle to provide a frictionless surface over which the vehicle travels and to provide obstacle clearing height when required. In some instances part of the pressurized air is diverted to drive the vehicle. In other instances separate or auxiliary drive means are used. The former means of propulsion has the advantage of using a common supporting and driving power source but the disadvantage of sacrificing supporting power for locomotion and vice versa in most instances.

Heretofore, air pressure losses incident to maintaining a normal obstacle clearing height have been considered a necessity in air supported vehicles. Although the height required to be maintained over relatively level surfaces is minimal, ocean travel has been said to require an elevation of twenty to forty feet to surmount ocean waves. Accordingly, the power requirements for marine use have caused skepticism in the practicality of a dual functioning power source for air support and locomotion in true amphibious vehicles.

One of the objects of this invention is to teach means which enable a conservation of supporting air pressure in air supported vehicles and accordingly more efficient use of supporting air power for propulsion purposes in marine vehicles as well as vehicles which travel predominately on land.

One means of conserving air supporting power, as taught by this invention, is to provide yielding closure members within the peripheral wall of the air supporting air chamber to enable the passage of travel obstructing means under the vehicle and through the chamber without requiring additional lift to pass thereover and with a minimum depletion of supporting air power as the obstacle passes thereunder.

The use of yielding closure means as hereinafter described is particularly adaptable for use on marine craft to pass the high crests of waves thereunder but is equally applicable to land traveling vehicles as regards occasional obstacles in an otherwise relatively unobstructed path.

We have found in the comparison of air supported vehicles for land and Water uses that although such vehicles are generally independent of the terrain over which they travel, and are thus in a true sense amphib ions, that certain structural modifications and differences in operation are advisable in marine craft.

Accordingly, another object of this invention is to teach an air supported vehicle particularly well suited for marine use while still equally amphibious in character.

In the foregoing respect, it is an object of this invention to teach a body construction for air supported vehicles similar to the catamaran construction of marine craft; that is, inclusive of spaced buoyant supports, to enable flotation of the vehicle without air supporting assistauce.

It is another object of this invention to teach that such an air supported vehicle include operative means between such buoyant supports to close the space therebetween and extend the supporting air chamber closer to the water surface for pressurization thereof and added buoyant support of the craft as used in the water.

It is also an object of this invention to teach that the; aforementioned supporting air chamber be capable of sufiicient pressurization to raise the buoyant supports and appreciably reduce the drag resistant character thereof. For beaching and land use the pressurization is intended to be capable of lifting the vehicle from the water and holding it supported thereover on the customary pad of air.

A further object of this invention is to teach having the buoyant side supporting means provide an air pressure seal by remaining just slightly within the water and thereby enabling a conservation of supportim air power for propulsion and locomotion purposes in marine use.

A still further object of this invention is to teach the use of a bow planing closure between the spaced buoyant supports at the front of the vehicle to surmount less forceful water waves and which is yieldingly mounted to pass insurmountable waves therepast without breaking the air supporting seal under the vehicle to any appreciable extent. A transom closure is also intended at the stern of the vehicle for cooperation with the bow closure.

These and other objects and advantages to be gained in the practice of this invention will be more apparent upon a reading of the following description of a working embodiment of the invention and study of the accompanying drawings wherein;

FIGURE 1 is a perspective view of a cargo carrying air supported amphibious vehicle.

FIGURE 2 is a front view of the amphibious vehicle of FIGURE 1 showing the bow closure member.

FIGURE 3 is a side plan view of the vehicle shown by FIGURE 1.

FIGURE 4 is a cross-sectional view of the amphibious vehicles of FIGURES 1-3, as seen in the plane of line IVIV in FIGURE 3, and showing the general construction thereof.

FIGURE 5 is an enlarged longitudinal and cross-sectional view through the front end of the amphibious vehicle of FIGURES 1-3 showing the air pressurizing means and general air flow path.

FIGURE 6 is an enlarged cross-sectional view of part of the amphibious vehicle of FIGURES 1-3 as seen in the general plane of line VIVI of FIGURE 3.

FIGURE 7 is an enlarged fragmentary end view of the stern of the amphibious vehicle of FIGURES 1-3.

FIGURE 8 is an enlarged fragmentary view of the stern of the amphibious vehicle of FIGURES 1-3 as seen from one side thereof.

FIGURE 9 is an enlarged top plan and detail view of the propulsion shutters and their means of control.

FIGURE 10 is a diagrammatic illustration of the amphibious vehicle of this invention afloat and without the benefit of air supporting power.

FIGURE 11 is a diagrammatic illustration of the amphibious vehicle of this invention and with air supporting power supplied thereto.

FIGURE 12 is a diagrammatic illustration of the amenemas phibious vehicle of this invention under air supporting power lifting it from the water and for land-borne use.

FIGURE 13 is a diagrammatic illustration of a predominantly marine craft, though also amphibious, using turbine exhaust gases for air supporting power.

FIGURE 14 is a diagrammatic illustration of an optional means of propulsion for use with the disclosed amphibious vehicle.

The amphibious vehicle of this invention meets the needs of a vehicle that can transport cargo and personnel over land, water and other surfaces generally incapable of supporting wheeled vehicles. This vehicle is intended to operate efficiently over all relatively unobstructed surfaces and to provide a single carrier for the transportation of cargo from its source to its final destination. The need for docking and transfer facilities is completely avoided and the lost time and material handling expense incident thereto are virtually eliminated.

The proposed vehicle is highly flexible and amazingly versatile for either or both land and water operations. While traveling over land it is supported on a cushion of low pressure, low velocity air in the manner of conventionally known air supported vehicles. Over water the vehicle is operated by maintaining a cushion of low pressure, low velocity air to support a major portion of the undersurface thereof clear of the water surface and thereby greatly reduce the drag. In both instances air is also used for propulsion and a high degree of maneuverability.

The air floatation principles provided in the hereinafter described amphibious vehicle permits more stable and seaworthy operation thereof. it also enables travel on debris-littered waterways, that are normally considered impassable, and travel over swamp and marsh land where even docking facilities are not feasible.

The combination floatation and propulsion principles incorporated in the vehicle of this invention enables large load carrying capacity at relatively high speeds with no sacrifice of buoyant support in attaining greater speeds or increased maneuverability.

Referring now to the drawings in further detail:

The amphibious vehicle 10 is shown in FIGURE 1 as being air-borne in the sense that it is supported clear of the land 12 and water M on an invisible cushion or pad of pressurized air escaping from its underside. In general appearance the vehicle lltl looks much like a barge having a large load carrying and, in this instance, open deck area 16. The usual stern and deck rails 18 and 20 are shown and a control cabin or pilot house 22 is shown near the bow of the vehicle.

The deck rails 20 may include removable or fold-down sections 24 for greater accessibility to the deck area 16 in loading and unloading the vehicle. These are shown only as retracted and forming part of the deck rail structure.

A pair of low pressure fan housings 26 and 28 are shown extending up over the deck area near each end of the vehicle. These enclose the power source for vehicle support and propulsion and will subsequently be described in greater detail. Basically, they induct sufiicient air to maintain a low pressure, low velocity condition within the body or hull 30 of the vehicle. This enables a controlled lift to be obtained and exhaust air to be used for propulsion and other control purposes via forwardly and rearwardly disposed shutter assemblies 32 and 34 on each side of the vehicle.

The vehicle hull 30 is a combination truss and monocoque construction of light weight material and includes lateral strut braces 36 as required for internal structural strength. The catamaran form of boat hull is employed and the midships section, between the fan housings 26 and 28, affords the major bridging strength. The underdeck area is open and unobstructed, except for the pressurizing fan duct outlets yet to be described. This provides the air collecting chamber 38.

Buoyant support is afforded the amphibious vehicle 10 when not under air supporting power, by means of the depending pontoon or outrigger-like support rails 40 provided on the underside of the hull 30 near each side there of. These side rail supports 40 are covered externally but may be open to the air collecting chamber 38. They may also be filled with styro-foam or other buoyant material as a precaution against puncturing, as shown by FIGURE 4.

An air distribution pad or platform 42 is mounted in parallel spaced relation below the deck 16 and in open spaced relation at its edges relative to the supporting side rails 40. This member is principally to assure an even distribution of the air flow from the fan housings within the air collecting chamber 38.

Under ordinary conditions, and without air supporting powder, the side rails 48 are the only part of the vehicle it? that extends below the water when the vehicle is afloat. However, the air distribution pad 42 is preferably of styro-foarn or other buoyant construction as an auxiliary means of floatation support.

The fan housings 26 and 28 include an intake housing 28' extending over the cargo deck area 16 and exhaust housing 44 extending below the deck level and within the air collecting chamber 38. The exhaust housing is supported on the inner structural cross beams 46. The intake housing is supported on the deck beams and aligned or connected to the exhaust housing.

A shielded housing 48 is provided concentrically within the intake housing 28 for the fan driving engine 50. The inner housing 48 is supported on radially disposed arms 52 connected to the outer housing wall. Concentrically disposed air directing rings 54- are disposed in the intake passage and protective screen coverings 5'6 and 58 are disposed over the open ends of the housing members mentioned.

The engine 519 may be of the aircraft engine type and, speaking generally of the disclosed amphibious craft It would have a continuous cruise rating of about 890 HP. and a maximum operating speed of about 2400 r.p.m. The engine is braced and supported within the upper end of the inner housing 48 and drives a multiple bladed fan 60 through a gear reduction box 62. The vertically disposed fan shaft is journalled within a bearing member 64 supported centrally within an inner conical wall 66 of the exhaust housing 44. This inner wall '66 serves to direct inducted air more uniformly Within the air collecting chamber 38 and may include openings (not shown) for the passage of engine cooling air therethrough and out the open upper end of the inner housing 48.

The air flow through the fan housings 26 and 28 is as shown by the arrow headed flow lines in FIGURES 5 and 6. The air is exhausted annularly into the air chamber space 38 and is distributed evenly therein by means of the distributer pad 42.

The depending buoyant supports 4d, at each side of the vehicle, form side wall extensions of the air collecting chamber 38 and, in combination with forward and rearwardly disposed closure members extending therebetween, provide a lower disposed air collecting space 68. The air distributing pad 42 is sufiiciently spaced from the support rails 40 so that the air flow and pressure buildup in the lower disposed chamber 68 is the same as in the chamber 38.

The forwardly disposed closure member between the side rails 40 is a bow door 70 which is hinged at its forward end, as at 72, and extends aft to provide a planing surface '74 on the underside thereof. The rearwardly disposed closure member is a transom door 76 hinged, as at 78, and opening downstream of normal boat travel.

The bow and stern closure members 79 and 76 are operative members which may be held in the solid line closed positions shown by FIGURES 5 and 8, or may be opened to the dotted line positions '70 and 76' shown. The closure members each have operative means such as the hydraulic actuators 80, engaged thereto for selective positioning thereof. They are also inclusive of a means, such as spring 82, for yieldingly biasing them in a closing position. Accordingly, the closure members 70 and 76 are responsive to an encounter with an obstacle in their path of travel and will yield to allow such an obstacle to pass thereunder.

The closure members 70 and 76 are preferably of a light weight, honeycomb or hexcell construction as shown by the cutaway section 84 of FIGURE 7. This atfords a buoyant character to the closure members which is particularly well suited for amphibious craft.

A low water wave 86 is shown in dotted outline form by FIGURE 5 as it raises the bow closure door 70 and passes thereunder. It will be appreciated that the bow door yields to the pressure of the on-coming wave without breaking the air-lock seal it provides with respect to the supporting air chamber 68. The water wave may cause an air loss within the valley of the wave, as at 88, but this loss is a consistent loss as the wave form travels down the vehicle side.

The use and effect of the bow and stern closure members will be subsequently described in further detail; both as regards air supported vehicles generally and the amphibious craft herein disclosed.

A suitable means of controlling the shutter assemblies 32 and 34, on both sides of the disclosed craft, and near the bow and stern thereof, is shown by FIGURE 9. It should also be mentioned that similar shutter means may be provided at the stern of the vehicle, as shown at 90 in FIGURE 7, with like controls.

Each shutter assembly includes a frame 92 within which are mounted a plurality of shutter members. The shutter members 32' are pivotally mounted on a vertical axis as at 94. They each include certain control braces 96 which are interconnected by connecting link members 98. An operating link 100 connects the last shutter member in a given set to a control link 102 which is itself pivotally mounted to the vehicle body or hull. An actuating device, such as the hydraulic cylinder 104, enables all of the shutters to be opened, closed and otherwise p0- sitioned simultaneously.

The shutter assemblies 32, 34- and 90 are disposed in the area of the plenum chamber 38 and above the normal water line of the disclosed amphibious craft. A side rail bumper 106 may run the length of the disclosed vehicle for dock mooring and other protection of the shutter frame as well as the vehicle itself.

In use, the shutter assemblies 32 and 34 are operatively interconnected by means coordinating their individual actuators 104 so that different control functions are obtainable. For example, the shutters when opened and disposed rearwardly will provide forward movement of the vehicle as the entrapped air from chamber 38 escapes rearwardly therethrough. Similarly, the shutters opened in the opposite direction would enable the vehicle to travel backwards. Shutters opened on one side of the vehicle will enable sideward movement of the craft and oppositely disposed shutter members opened at the front and rear of the craft will enable it to turn on its own axis.

The shutter members 90 in the stern of the disclosed craft may be used like a rudder under certain conditions. Generally, however, such control means is best used during engine warm-up when all shutters are feathered outward and no vehicle movement is desired, or in slow dock maneuvering, cross-wind crabbing, or the like.

The rear transom or closure member 76 at the stern of the disclosed vehicle also may be used as a means of air exhaust and vehicle control in certain instances. The vehicle movement that is or is not obtained will of course be dependent upon the effort of the exhaust gases as compared to the drag of the vehicle when afloat and which if any of the other control shutters are in use.

It is well to point out at this time that the air loss for propulsion of the disclosed vehicle, when afloat, is not a depletion of its supporting power as when the vehicle is actually air borne. An air borne vehicle of this type requires sufficient air pressurization power to offset depletion due to the air flow loss from under the vehicle; and the more ground clearance that is required, the more air pressurizing power that is needed. In this amphibious vehicle very little power is required to provide the floatation support or to maintain it. Accordingly, once the vehicle is pressurized for floatation the power source i available for propulsion purposes.

Referring to FIGURES lOl2:

The disclosed amphibious vehicle will ride dead in the water substantially as shown by FIGURE 10. The catamaran hull construction causes the side rail supports 40 to float the craft and provides a shallow air space under the air distribution pad 42. The size and shape of the side supports 40 determine the floatation characteristics of the disclosed vehicle as with conventional marine craft of the catamaran type.

When the air pressurization fans are placed in operation the low pressure, low velocity condition is quickly built up in the air collecting chamber 38. Since there is no restriction to air flow and pressure buildup in the space 68 under the air distribution pad 42 the vehicle rises in the water and soon assumes substantially the air floated position of FIGURE 11.

With all of the air venting shutter means closed the disclosed craft can be caused to pop out of the water and ride on its pressurization pad much as shown over solid land by FIGURE 12.

The side rails 46 of the disclosed craft need only be immersed to the extent necessary to maintain a pressurization seal. Under air floated conditions the side rails do not serve as a floatation means of themselves. Accordingly, on inland waters and relatively smooth seas the craft would draw only about six inches. Even under adverse weather and sea conditions requiring a greater draft to maintain the pressure seal, the side rails would not impose any seriou drag on the vehicle due to their water cleaving shape.

The floatation supported vehicle of F iGURE 11 has the bow closure 70 and the stern closure 76 biased in a closing position but yieldable in the course of forward vehicle movement. Since the closure members are buoyant and also yield to the pressure of water passing thereunder, they assume a wave riding position which affords the least resistance to forward movement and at the same time always preserves the pressurization seal of the air supporting chambers. The bow closure 70 will rise to pass the crest of an oncoming wave and will close thereafter. The wave form will travel through the chamber 68 and pass under the stern closure 76. Thus the amphibious craft will not be required to surmount each and every wave it encounters nor will its forward movement be appreciably deterred thereby.

In air supported use over more solid terrain, the disclosed vehicle normally has the bow and stern closures 7t) and 76 in their closed positions. However, as mentioned previously, these same closure members, or like means, could be used to pass obstructions under an airborne craft.

It is also to be noted that the air gap at the ends of the air distribution pad 42 and between the pad and the side rail supports 4% might be closed in emergency conditions to provide a closed air chamber for buoyant support. This would be in addition to the buoyant character of the air distribution pad previously suggested.

Other innovations include using the exhaust from a gas driven turbine engine M8 to pressurize a chamber space 68 via duct work 110, as shown by FIGURE 13. This would be essentially a marine vehicle although the propeller drive 112 could be vertically retractable for simple beaching operations and the like. The craft shown in FIGURE 13 has the catamaran construction including the side rails 40', the air distribution and auxiliary floatation pad 32, and the bow and stern closures 70 and 76.

Since the full power available for land use is not required for marine use, another innovation is that shown by FIGURE 14. In this instance the after fan assembly 114 is shown as pivotally mounted and the duct work thereof closed in order to use the fan for direct forward drive. In all other respects the craft is essentially as pre viously described.

We claim:

1. A ground etfect vehicle for amphibious use; said vehicle comprising a body portion having an upper deck ,With downwardly extending Walls to form a chamber having an open downwardly-facing bottom side, said body walls including a pair of parallel side walls and bow and stern walls with said side walls having a lightweight construction to provide the vehicle with an upward buoyant force when immersed in water, each of said bow and stern walls having their lower edges terminating above the lower edges of the side walls; and bow and stern members extending between the side Walls and being pivotally connected to the lower edges of the bow and stern walls espectively and depending therefrom so that the pivotal support for said bow and stern members serves to facilitate the passage of water waves under the vehicle between its side walls; means to supply air under pressure to the upper portion of said chamber; a generally horizontal partition disposed across said chamber above its open bottom side and below the point of said air supply to said chamber, said partition also having an impervious lightweight construction to provide the vehicle with an upward buoyant force when immersed in water and being spaced from at least a portion of the walls of said chamber to leave a gap therebetween for flow of air from above said partition thru said gap to the underside of said partiears-3 tion to provide a pressure under the partition sufiicient to raise the vehicle a small distance; at least certain of the vehicle walls having openings disposed above the partition for air flow outwardly therethrough in a generally horizontal direction to provide the vehicle with horizontal thrust; and means supported by the vehicle walls and selectively operable for controlling said wall openings to control the air flow therethrough', thereby regulating the vehicle thrust.

2. A ground effects vehicle as claimed in claim 1 and including means operatively connected to said bow and stern pivotal members for locking said members against pivotal movement in a position suitable for operation of the vehicle over land.

References Cited in the file of this patent UNITED STATES PATENTS 1,726,882 Boerner Sept. 3, 1929 1,819,216 Warner Aug. 18, 1931 2,322,790 Christadoro June 29, 1943 2,444,318 Warner June 29, 1948 2,955,780 Hulbert Oct. 11, 1960 2,969,032 Pinnes Jan. 24, 1961 FOREIGN PATENTS 219,133 Australia Nov. 24, 1958 OTHER REFERENCES Publication: The Autocar; Aug. 21, 1959; pp. 42, 43, 44.

Publication: Curtiss-Wright Model 2500 Air Cor. (Received in Div. 47 on Jan. 19, 1960.)

Publication: Aviation Week; July 6, 1559; pages 115 and 116. 

